A class of disorders may be characterized as tissue remodelling-associated conditions, and includes cancers, arthritic conditions, obstructive disorders, degenerative disorders, and problematic wound-healing and ulcerative disorders. Paradigmatic among these is prostate cancer (CaP), the leading source of new cases of cancer in men in this country, and the second leading cancer cause of cancer death after lung cancer. Over 40,000 Americans are estimated to have died of CaP in 1995, and about 244,000 new cases of prostate cancer were detected (Cancer Facts and Figures--1995, American Cancer Society, Inc., 1995) and these numbers have increased annually at an alarming rate. Further, the rate of appearance of prostate cancer in African-American men is 37% higher than for their white counterparts (Jaroff, L. (Apr. 1, 1996), Time).
The current primary diagnostic tool for disorders of the prostate is measurement of the level of prostate-specific antigen (PSA) in blood, which in normal men ranges from 0 to 4 nanograms/milliliters. Prostate enlargement, a condition known as benign prostatic hyperplasia (BPH), is found in about half of men over age 45. With BPH, PSA levels rise in proportion to prostate size, possibly obscuring diagnosis of CaP. In addition, a significant proportion of men with CaP have normal PSA levels. The PSA test is somewhat non-specific for distinguishing CaP and BPH, and produces a degree of false negative results (Garnick, M., (1993), Am. Inst. Med, 118:804-818). Further, the PSA test is somewhat invasive, requiring the subject to give a blood sample, a procedure that requires trained personnel, in the setting of a doctor's office or clinic. The PSA test, a major advance over previous procedures, thus leaves much to be desired.
CaP is treated by surgery, radiation therapy, cryotherapy or implantation of radioactive seeds, or a combination of these procedures. In choosing one of these treatments, consideration is also taken of possible sequelae that impact negatively on quality of life, such as temporary or long-term incontinence and impotence. Further, following surgical or chemotherapeutic treatment, production of testosterone is suppressed hormonally, to discourage metastases in the CaP patient. Hormonal suppression is found to be effective for several years duration, however cancer cells that have metastasized eventually become resistant to the drugs of hormonal suppression. CaP metastasis to other sites is inevitably fatal. Only a small percent of men with microscopically-detectable CaP progress to metastatic cancer and actually die of this disease. A current medical approach, particularly for the elderly, is "watchful waiting", wherein tumors are not treated but rather monitored for progression.